[1.05] Mass-period Distribution of Extrasolar Planets and its Dependence on Host Star's Metallicity

We carried out simulations to predict the distributions of
masses and semi major axes (periods) of extra solar planets,
modeling the accretion of cores of giant planets from
planetesimals, gas accretion onto the cores, and their
orbital migration. We dopted a working model for nascent
protostellar disks with a wide variety of surface density
distributions, which are comparable to those inferred from
the observations of circumstellar disks of T Tauri stars.
Since planets' masses grow rapidly from 10 ME to 100
ME, we predict that the gas giant planets rarely form
with asymptotic masses in this intermediate mass range at
< 3AU. We refer to this deficit as a ``planet desert." We
also predict that the frequency of gas giant planets that
are detectable with current adial velocity search is greatly
enhanced in metal-rich protostellar disks, which is
consistent with the observation. Protoplanetary cores can
grow to several Earth masses prior to the disk gas depletion
in such environment and these large masses are required for
the cores to initiate rapid gas accretion and to transform
into giant planets. We also suggest that more than ninety
percent of planets migrated to the vicinity of their host
stars is perished.

The author(s) of this abstract have provided an email address
for comments about the abstract:
ida@geo.titech.ac.jp